Switch back to using one transfer roller voltage

Signed-off-by: Milind Upadhyay <milind.upadhyay@gmail.com>
Change-Id: I42bdfec3813f009aa89066d4682658db956a5a89
diff --git a/y2022/control_loops/superstructure/superstructure_output.fbs b/y2022/control_loops/superstructure/superstructure_output.fbs
index af6c292..a4460e2 100644
--- a/y2022/control_loops/superstructure/superstructure_output.fbs
+++ b/y2022/control_loops/superstructure/superstructure_output.fbs
@@ -26,8 +26,9 @@
   // positive is pulling into the robot
   roller_voltage_front:double (id: 6);
   roller_voltage_back:double (id: 7);
-  transfer_roller_voltage_front:double (id: 8);
-  transfer_roller_voltage_back:double (id: 9);
+  transfer_roller_voltage:double (id: 8);
+  // Only using one transfer roller voltage now
+  transfer_roller_voltage_back:double (id: 9, deprecated);
 }
 
 root_type Output;